4-{8 N-(2-methyl-3-hydroxy-4-hydroxymethyl-5-pyridylmethyl)-piperazino{9 -p-fluoro-butyrophenone

ABSTRACT

WHEREIN: A is the selected acid and N IS AN INTEGER TAKING THE VALUES 1, 2, 3 AND 4. These compounds may enter into anti-hypertensive drugs. This invention relates to the preparation and use of new piperazine derivatives, the therapeutically acceptable salts of 4-((2-methyl-3-hydroxy-4-hydroxymethyl)-5-pyridyl N-methyl-N&#39;&#39;piperazinyl)-p-fluoro-butyrophenone of the formula:

United States Patent [1 1 Esanu 4- N-( 2-METHYL-3-HYDROXY-4- HYDROXYMETHYL-S-PYRIDYLMETHYL PIPERAZINO1-P-FLUORO- BUTYROPHENONE [75] Inventor:

[73] Assignee: Societe dEtudes de Produits Chimiques, Molineaux, France 22 Filed: Mar. 15,1974

21 Appl.No.:45l,5l3

Andre Esanu, Paris, France Primary ExaminerDonald G. Daus Assistant Examiner-Jose Tovar Attorney, Agent, or FirmEyre, Mann & Lucas 1 Sept. 2, 1975 5 7] ABSTRACT This invention relates to the preparation and use of new piperazine derivatives, the therapeutically acceptable salts of 4-[(2-methyl-3-hydroxy-4-hydroxymethyl)-5-pyridyl N-methyl-N'-piperazinyl]-p-fluorobutyrophenone of the formula:

wherein:

A is the selected acid and n is an integer taking the values 1, 2, 3 and 4.

These compounds may enter into anti-hypertensive drugs.

2 Claims, N0 Drawings 4-[N-(2-METHYL-3-I-IYDROXY-4- HYDROXYMETHYL-S-PYRIDYLMETHYL)- PIPERAZINO]-P-FLUORO-BUTYROPHENONE NEW PIPERAZINE DERIVATIVES AND THEIR PROCESS OF PREPARATION This invention relates to new piperazine derivatives and their process of preparation. The new derivativesaccording to this invention are the salts of 4-[(2- methyl-3-hydroxy-4-hydroxymethyl)-5-pyridyl N- methyl-N-piperazinyl]-p-fluoro-butyrophenone with therapeutically acceptable acids. Their formula is:

cu orr.

on CH2'N wherein:

A is the selected acid and n is an integer taking the values 1, 2, 3 or 4. Usually selected acids are hydrochloric, acetic, any of the chloracetic, benzoic, maleic, for instance.

The invention will be illustrated by the example of, the maleicsalt.

The empirical formula of this derivative is C ,,H O N F and its molecular weight is 749.7. The derivative is beige-yellow powder melting at 127/ 1 C, soluble in water at room temperature, soluble in warm ethanol and octanol and insoluble in chloroform. It shows interesting hypotensive and adrenolitic properties, with a marked -blocking action associated with a hypotensive action comparable and even superior to that of reserpine.

The above derivative may be prepared according to this invention by reacting in xylene, 3,4-

isopropylidenyl-S-piperazinylpyridoxine and 4-chlorop-fluoro butyrophenone in the presence of triethylamine, according to the following reaction scheme:

The compound thus obtained is reacted with maleic acid which leads first to the breakingof the isopropylidene bridge and secondly to the formation of a salt with 3 moles of maleic acid per mole of the pyridoxine derivative.

The preparation is examplified asfollows.

EXAMPLE In a l0 litre reactor fitted with stirring means, cooling and heating means there were poured 530 g (L mole) of 3,4-isopropylenyl 5-piperazinyl-pyridoxine, 480 g (2.4 moles of 4-chloro-p-fluoro-butyrophenone, 240 g (2.4 moles) of triethylamine and 5 litres of anhydrous xylene. After stirring there was a complete dissolution of the ingredients in the xylene and the mixture was refluxed for 15 hours during which time the mixture turned brown and a precipitate was formed. This precipitate was separated, filtered, dried washed and treated with 5 litres of a solution of petroleum ether in diethyl ether which gave after drying 550 g of a product. This product was then recrystallised from isopropanol. Yield 460 g ofa product melting at 1 14C to C, being 3,4-isopropylidenyl-pyridoxin-5-yl-4- piperazin-l-yl-p-fluoro-4-butyro-phenone. This compound was then treated with maleic acid in the same 10 litre reactor as above. There were poured into this reactor 6 litres of distilled water containing 2% of ethano], 400 g (3.4 moles) of maleic acid and 300 g (0.68 mole) of the isopropyliden derivative obtained in the previous step. The mixture was refluxed for 30 minutes then evaporated to dryness under reduced pressure. The residue was treated with ethyl alcohol and recrystallized from 3 litres of pure ethyl alcohol. Yield 420 g of a beige-yellow product melting at 127/130C the analysis of which corresponds to the formula C l-I O N F. The 3,4-isopropylidenyl-5-piperazinylpyridoxine was obtained by the reaction of monocarbosyethyl piperazine on 3,4-isopropylidenyl-5-chloropyridoxine in anhydrous dimethyl formamide and in the presence of potassium carbonate. The 3,4- isopropylidenyl-S-chloro-pyridoxine was obtained by chlorination by SO CI of the 3,4-isopropylidene pyridoxine which was obtained as described in previous US. Pat. No. 3,717,636.

The anti-hypertensive activity of one of the compounds of the invention, as the one described in the above mentioned example, which is named hereunder test compound or PxPlFB-M has been tested in renal (Goldblatt) and metacorticoid (DOCA) hypertensive rats, compared to the standard preparations of guanethidine and -methyldopa. A complementary investigation has been undertaken on normally hypertensive rats of the Okamoto strain. For the main investigation there were used male albino rats (CFY strain) obtained from Carworth Europe. Implant pellets of Desoxycorticosterone acetate (DOCA) were obtained from Organon Laboratories Ltd. Guanethidine sulphate (Ismeline tablets, CIBA), -methyldopa (Aldomet tablets, MSD) subsequently referred to as methyldopa METHODS Preparation of Goldblatt hypertensive rats This method is similar to that described by Goldblatt, H., Lynch, J., Hanzal, R. F. and Summerville, W.

W. (1934) J. Exp. Med., 59, 347-379 Male rats of Carworth CFY strain (-140 g) were used. Under sterile conditions, and using ether anaesthesia, a costolumbar incision was made and the left kidney was retracted towards the abdomen. The renal pedicle was exposed and the artery dissected clean. A silver clip was placed around the artery, near the abdominal aorta. The right kidney was removed through shown in Table 1. The percentage change of mean pressure from the pre-dose vlaue is also shown in Table 1.

The group mean systolic and diastolic blood presa second incision. The body wall was sutured with cat- 5 sures prior to and at various times after drug adminisgut, and the skin closed with autoclips. Each rat was tration are shown in Table 2 for Goldblatt rats, and then given 30,000 1U Procaine Penicillin G by the in- Table 3 for DOCA rats.

tra-muscular route. Hypertension developed slowly The complementary investigation on OKAMOTO over a period of 6-9 weeks. hypertensive rats was undertaken by the same technic Preparation of DOCA hypertensive rats 10 as above with the unique dose of 25 mg/kg for the stan- This method is similar to that described by Green, D. dard and test compounds.

M., Saunders, F. .1., Wahlgren, N. & Craig, R. L. From an examination of the data one can make the (1952) Am. J. Physiol, 170, 94-106 following comments.

Male rats of Carworth CFY strain (90-120 g) were 1. The two standard compounds, methyldopa and used. Under sterile conditions, and using ether anaesguanethidine, and the test compound PxPlFB-M all thesia, an incision was made on the left side of the absignificantly reduced the blood pressure of Golddominal wall of the rat and the left kidney removed. A blatt, DOCA and OKAMOTO hypertensive rats. 50 mg pellet of DOCA was implanted sub cutaneously. 2. Methyldopa had approximately the same antihy- The body wall was sutured with catgut, and the skin pertensive activity in Goldblatt and DOCA rats and closed with autoclips. Each rat was then given 30,000 the best one IU Procaine Penicillin G by the intramuscular route. 3. PxPlFB-M appears to be the most active on Drinking water was replaced by 0.8% sodium chloride OKAMOTO rats. and 0.1% potassium chloride in tap water. Hyperten- TOXICITY sion developed slowly over a period of 5-8 weeks.

Experimental design Toxicity on mice showed a value of 1.0 g per 0s and The rats were deprived of food but not water for 18 0.5 g intraperitoneously. hours prior to an experiment. The blood pressure of each rat was recorded before, and at 2, 4, 8 and 24 PRESENTATION hours after drug administration. Compounds were sus- Any suitable form can be used and for instance, tabpended in 1% carboxymethylcellulose and adminislets are obtained from the following preparation (parts tered at a dose volume of 10 ml/kg. Groups of 8 aniin weight): mals were used. Blood pressure was measured indirectly from the caudal artery by a modification of the S ZEE 28 method described by Microcrystalline cellulose 31.5

Ben-Ziv, G., Weinman J. and Sulman, F. G. (1964) a l 25 Arch. int. Pharmacodyn, 149, 527-535. dgnesmm mama 0(1) Tablets were of 100 mg (breakable) containing 50 RESULTS mg of active product. Normal doses to be used daily in The mean blood pressure for each group prior to, and human therapy are between 25 and 500 mg and more at 2, 4, 8 and 24 hours after drug administration is generally between and 250 mg.

TABLE 1 The mean blood pressures of each group taken before and at 2, 4, 8 and 24 hours after drug administration and percentage change of mean blood pressure from the value before drug administration (0 hr.)

Model of Oral Mean BP (mmHg) at time change in mean HP from 0 hr hyperten Compound dose sion mg] kg 0 hr 2 hr 4 hr 8 hr 24 hr 2 hr 4 hr 8 hr 24 hr Goldblatt 1 CMC (Control) 252 253 239 245 247 0.4 5.2 2.8 2.0 Methyldopa 200 189 138 121 118 186 27.0 36.0 37.6 1.6 Methyldopa 67 236 182 171 176 238 22.9 27.5 25.4 0.8 Guanethidine 25 200 178 173 183 187 11.0 13.5 8.5 6.5 Guanethidine 8.3 241 239 230 226 235 0.8 4.6 6.2 2.5 PxPlFB-M 25 204 172 159 172 185 15.7 22.1 15.7 9.3 PxPlFB-M 8.3 256 237 232 231 251 7.4 9.4 9.8 1.9 DOCA 1% CMC (Control) 229 220 206 216 219 4.0 10.0 5.7 4.4 Methyldopa 200 217 152 139 191 30.0 36.0 49.3 12.0 Methyldopa 67 227 228 161 142 223 0.4 29.1 37.4 1.8 Methyldopa 25 208 194 203 203 204 6.7 2.4 2.4 1.9 Guanethidine 25 237 172 174 159 213 27.4 26.6 32.9 10.1 Guanethidine 8.3 243 217 217 202 228 10.7 10.7 16.9 6.2 PxPlFB-M 25 220 196 188 217 10.9 14.5 27.3 1.4 PxPlFB-M 8.3 216 214 208 203 212 0.9 3.7 6.0 1.9

Mean blood pressure is taken as the diastolic blood pressure plus of the difference between the diastolic and systolic blood pressures.

TABLE 2 Group mean systolic and diastolic blood pressure of Goldblatt hypertensive rats, before, and at 2. 4. 8 and 24hours after drug administration Systolic & diastolic blood pressure (mmHg) (0S.E. Oral dose 7 Compound mg! 0 hr 2 hr 4 hr 8 hr 24 hr Systo- Diasto- Systo- Diasto- Systo- Diasto- Systo- Diasto- Systo- Diastolic' lic lic 11c lic lic 11c :lic lic lie 1% CMC (Control) 262 231 262 235 251 215 258 218 259 223 (013.0 (010.9 (019.1 (016.8 (011.4 (09.9 (014.8 (014.6 (012.1 (012.3 Methyldopa 200 200 166 145" 124" 129*" 106* 128*" 99*" 194 170 (011.3 (011.7 (0 6.8 (06.0 (012.3 (010.3 (013.8 (012.3 (016.7 (014.0 Methyldopa 67 246 215 192* 161* 181" 152* 188" 1531? 254 206 (016.0 (015.5 (022.9 (021.3 (025.8 (023.6 (020.4 (017.9 (022.1 (020.8 Guanthedine 212 177 187 160 184" 152 196" 158* 200 162 (010.1 (0 8.8 (010.4 (0 8.9 (0 8.0 (0 6.9 (012.1 (010.1 (011.8 (0 9.8 Guanthedine 8.3 255 213 254 209 244 202 243. 191 247 212 (019.6 (014.7 (017.4 (013.5 (015.3 (014.0 (014.8 (013.8 (018.5 (015.3 PxPlFB-M 25 214 185- 182 151 167" 142** 183 .150** 196 164 (012.8 (012.3 (020.5 (015.2 1 (011.7 (010.0 (013.2 (010.9 (012.8 (011.0 PxPlFB-M 8.3 271 227 247 217 246" 203" 247*? 200* 266' 221 Significance of difference from the predose value (paired t' test) TABLE 3 Group mean systolic and diastolic blood pressure of DOCA hypertensive rats, before, and at 2, 4, 8 and 24 hours after drug administration Systolic & diastolic blood pressure (mmHg) (0S.E. 0 hr 2 hr 4 hr 8 hr 24 hr Oral Compound dose mg/ Systo- Diasto- Systo- Diasto- Systo- Diasto- Systo- Diasto- Systokg 11c lic lic lic lic lic lic lic lie 1% CMC (Control) 244 198 236 189 218 183 229 189 229 (013.0 (012.5 (015.7 (010.0 (010.0 (09.4 (09.1 (09.6 (013.3 Methyldopa 200 229 193 169* 118 148" 117* 95* 202 (019.2 (014.8 (022.1 (024.0 (019.4 (015.8 (0 9.4 (0 8.2 (010.8 Methyldopa 67 239 202 246 192 174 134* 154" 119* 237 (015.2 (011.4 (017.3 (014.2 (08.3 (011.2 (010.6 (012.5 (016.4 Methyldopa 25 220 183 205 172 215 178 216 176 214 (012.4 (012.4 (016.1 (018.0 (015.0 (015.8 (011.2 (012.6 (0 7.4 Guanethidine 25 251 209 185* 151* 173" 130" 224 (012.5 (012.2 (019.2 (018.6 (017.7 (015.9 (014.1 (013.7 (015.1 Guanethidine 8.3 258 212 232* 188 232 188 214* 179* 242 (016.8 (011.3 (013.0 (011.0 (018.6 (016.7 (013.2 (09.7 (0 9.9 PxPlFB-M 25 231 198 211 166*" 203 157" 169* 142* 232 (015.0 (011.3 (012.7 (010.4 (010.6 (0 6.8 (015.1 (013.4 (013.7 PXPIFB-M 8.3 228 191 223 196 219 187 216 178 223 Significance of diflerence from the predose value (paired t test) TABLE 4 Means of systolic and diastolic blood pressure (in rnmHg before and after compound treatment Blood pressure (Hours after treatment) TABLE Mean blood prcssurc of groups of Okamoto rats with the percentage of the blood pressure modification Blood pressure (Hours after treatment) l. A therapeutically acceptable acid addition salt of a l5 compound of the formula Page 1 of 5 UNITED STATES PATENT OFFICE QE'HFECATE OF CORRECTION PATENT NO. 5,905,088 DATED i September 2, 1975 |NVENTOR(S) 1 Andre Esanu It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1 cancel lines 5 and 6.

Column 1 line 10,- "N" should read N" Column 1 line 37, "blocking" should read a-blocking Column 2, line 52, -=methyldoap"-' should read a methyldopa o Column 2, line 599 "'='-=methy1dopa-- should read I M a methyldopa o Col 3 and cancel Table 1 as shown and substitute the attached Table 1 a 7:11. 1 5 and 6, cancel Tables 2, 3 and as shown and substitute the attached Tables. 7 Col 7, cancel Table 5 and substitute the attached Table. Column 7,, line 13, cancel "2" and insert 2 at the beginning of line 17.,

' Signed and Scaled this v [SEAL] mflmth Day-of July 1976 RUTH C. MASON Arresting Officer C. MARSHALL DANN (ommm'iemer p/Pqrent: and Trademark:

Patent No. 3,903,088

TABLE 4 Page 5 of 5 Means of z-zystolic and diastoiie blend pressure-'2 (in before and aite'r compnund treatment Blood pressure nizompound n (Hnurs after treatment) w'methyldopa a t ysto'lic 256 2:1 193 17 M236 tag/kg Diastolis 2} i 1 75) l 6g L4? EQZ lnfih i ffih f g t l ilz flla k 170 223 210 251 was/kg a s. 1 .2- 52. --1-1 J 2. 2. PQQP'ZFEQJ G syszoi c. 239 m 167 177 203 25 mgikg Diastnlic 212 155 Mi 146 169 TABLE 5 Mean blood pressure of groups of Okamcto rats with the percentage of the blood pressure modification Blcwd pressure cnmpound :1 (Hours after treatment) azgethyldopa 6 blond press 23 200 1 83 266 226 "55 mg/kg modificat. 14.5 -21 s -;g a ;3 z

PxPIFB-M 6 blood press. 230 no 167 195 2% mg/kg 2 modificat. "-26.1 --31 .3 27.4 -15.2 

1. A THERAPEUTICALLY ACCEPTABLE ACID ADDITION SALT OF A COMPOUND OF THE FORMULA 